Talk:Well-defined

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Mathematics Portal This article is within the scope of WikiProject Mathematics, which collaborates on articles related to mathematics.
Mathematics rating:	Stub Class	Mid Priority	Field: Foundations, logic, and set theory
Please update this rating as the article progresses, or if the rating is inaccurate. Click to show/hide comments. Please add to or update the comments to suggest improvements to the article. Cronholm144 06:36, 21 May 2007 (UTC)

a good example from group theory is when you define something on an equivalence class in terms of one of its members. Naturally, you need to get the same result no matter which member was chosen. -- Tarquin 21:01 26 Jun 2003 (UTC)

Yes, this is a "canonical" meaning of "well-defined", when certain operations or functions, more generally, don't depend on choice of representatives. This precise meaning isn't really articulated in the article here. Revolver

It would be nice to have a specific example of what you need to verify in order for a function to be "well defined".

Example added, although possibly you may want more detail. Geometry guy 11:06, 14 February 2007 (UTC)